package com.lagou.utils;

import com.alibaba.druid.pool.DruidDataSourceFactory;

import javax.sql.DataSource;
import java.io.InputStream;
import java.sql.Connection;
import java.sql.ResultSet;
import java.sql.SQLException;
import java.sql.Statement;
import java.util.Properties;

public class DruidUtils {
    // 定义成员变量
    public static DataSource dataSource;

    // 静态代码块
    static {
        try {
            // 3、创建属性对象
            Properties p = new Properties();
            // 4、加载配置文件
            InputStream inputStream = DruidUtils.class.getClassLoader().getResourceAsStream("druid.properties");
            // 5、读取配置信息
            System.out.println(p);
            p.load(inputStream);

            // 通过工厂类获取连接池对象
            dataSource = DruidDataSourceFactory.createDataSource(p);
        } catch (Exception e) {
            e.printStackTrace();
        }

    }

    public static void main(String[] args) throws SQLException {
        System.out.println(DruidUtils.getConnection());
    }

    //获取连接的方法
    public static Connection getConnection() {

        try {

            return dataSource.getConnection();

        } catch (SQLException e) {
            e.printStackTrace();
            return null;
        }
    }

    //获取Druid连接池对象的方法
    public static DataSource getDataSource() {
        return dataSource;
    }


    //释放资源
    public static void close(Connection con, Statement statement) {

        if (con != null && statement != null) {
            try {
                statement.close();
                //归还连接
                con.close();
            } catch (SQLException e) {
                e.printStackTrace();
            }
        }

    }

    public static void close(Connection con, Statement statement, ResultSet resultSet) {

        if (con != null && statement != null && resultSet != null) {
            try {
                resultSet.close();
                statement.close();
                //归还连接
                con.close();
            } catch (SQLException e) {
                e.printStackTrace();
            }
        }

    }
}
